The ideal hybrid, the Instinct is built on the same sole as Asics's popular Gel-Speedstar road shoe but with the addition of a toothy bottom. This shoe delivers an impressive combination of cushioning and traction. "They performed well on most surfaces and were comfortable enough to wear on 25-mile runs," says Gary Long, a wear-tester from Reading. Some testers, though, were concerned that the Instinct's sole was too soft and failed to provide enough protection from sharp debris on rugged surfaces.

The Mission has a firm but smooth heel-to-toe transition, due in part to an outsole that stays in contact with the ground through the gait cycle. As the scan below shows, some runners will find the Mission snug in the heel.

BOTTOM LINE: A flexible shoe suited for trails and short stretches of road.

Soft underfoot, the Grit still offers good impact protection for runs on the road or on hard-packed trails—an impressive trait considering the shoe's low profile (a 28.5 mm heel height versus 35 mm for the average running shoe). One wear-tester, Brian Boos of East Lansing, describes the Grit as "a racing flat with some funky tread; not bulky like other trail shoes." A number of testers appreciated the Grit's lightness, but some said the extremely breathable upper let in too much cool air on cold runs and too much water during rainy outings.

The Fuji Racer, with its thin, flexible plate under the forefoot, provides considerable protection from sharp, off-road obstacles. That said, the forefoot is exceedingly firm, as evidenced by our Shoe Lab data. On the opposite end of the shoe, the Racer's heel offers sufficient cushioning and more than enough comfort. "The heel fit was excellent without needing to use the extra lacing holes that many of us women often need to," says Melanie Marinaccio, a wear-tester from Reading. Some testers pointed out that the drainage holes, a smart way to move loads of water out of the shoe, let in water. "On wet days, it didn't take long for the bottom of your feet to get wet," says Pierre Sirois of East Lansing.

BOTTOM LINE For lightweight, efficient runners who want to run fast on dry trails.

The lightest shoe in this guide, the 110 has a protective plate under the forefoot and sticky rubber outsole lugs for traction on wet trails. The upper's flexible material backed with mesh gives a second-skin feel that testers took to right away. What the 110 lacks is cushioning, making it better suited for racing than heavy-duty training.

BOTTOM LINE Delivers excellent flexibility and traction at a good value.

The Neo's 4.5 mm hard-rubber, tooth-like lugs provide real-deal traction, but because of the low sole height, the shoe offers no impact protection. Testers did find the shoe's fit on the mark. "There's ample room in the toebox to allow your foot to work on challenging surfaces," says Shaun Luther, a Reading wear-tester. Female testers also liked how the Neo's ankle collar locked their heels in place.

BOTTOM LINE For runners who want a minimal shoe with a roomy forefoot.

The Lone Peak's nearly zero drop—the heel and forefoot are level—is intended to promote a more natural transition from heel-strike to toe-off. Our testers agreed. "Initially I had to work hard to push off the ground, but once I got used to that, they felt great," says Sue Jackson of Reading.

Though relatively new to the trail-shoe market, Scarpa (known for mountaineering boots and rock-climbing shoes) impressed several of our testers with the lightweight and flexible Spark. "They are stable and comfortable. I liked them more than I expected," says Gerald Hanson of East Lansing. The shoe offers impressive protection from sharp trail obstacles, thanks to a plate under the forefoot and wide overlays at the base of the upper. With all that, the shoe weighs just 9.7 ounces (for a men's size 9). Another nice feature: The laces are 100 percent recycled plastic, and the out-sole is made of 25 percent recycled rubber.

BOTTOM LINE A lightweight trainer ideal for steep, shale-covered trails.